Đề 6 – Bài tập, đề thi trắc nghiệm online Hóa hữu cơ 1

1. How many stereoisomers are possible for 2,3-dichlorobutane?

A. 1

B. 2

C. 3

D. 4

2. Which of the following is a nucleophile?

A. BF3

B. AlCl3

C. NH3

D. H+

3. Identify the hybridization of the oxygen atom in water (H2O).

A. sp

B. sp2

C. sp3

D. dsp2

4. Which of the following alkyl halides will undergo SN2 reaction fastest?

A. (CH3)3CBr

B. (CH3)2CHBr

C. CH3CH2Br

D. CH3Br

5. Which of the following is an example of a protic solvent?

A. Acetone

B. Diethyl ether

C. Dimethylformamide (DMF)

D. Water

6. Identify the strongest acid among the following.

A. CH3CH2OH

B. H2O

C. CH3COOH

D. CH3CH3

7. Which of the following is a polar molecule?

A. CCl4

B. CO2

C. BF3

D. CHCl3

8. What is the geometry around the carbon atoms in ethene (C2H4)?

A. Linear

B. Tetrahedral

C. Trigonal planar

D. Bent

9. What is the major product of the reaction of 2-butene with HBr?

A. 1-bromobutane

B. 2-bromobutane

C. 1,2-dibromobutane

D. Butane

10. Which of the following reactions is an example of electrophilic addition?

A. Combustion of methane

B. Reaction of ethane with chlorine under UV light

C. Reaction of ethene with HBr

D. Saponification of ester

11. Identify the functional group present in acetic acid (CH3COOH).

A. Alcohol

B. Ketone

C. Carboxylic acid

D. Ether

12. What is the relationship between diastereomers?

A. They are mirror images of each other.

B. They are non-superimposable and non-mirror images.

C. They are superimposable mirror images.

D. They have the same physical properties.

13. Which of the following is a secondary alcohol?

A. Methanol

B. Ethanol

C. 2-Propanol

D. 2-Methyl-2-propanol

14. Which of the following is a geminal dihalide?

A. 1,2-dichloroethane

B. 1,1-dichloroethane

C. Chloroethane

D. Tetrachloroethane

15. Which factor primarily determines the boiling point of alkanes?

A. Functional group

B. Molar mass

C. Polarity

D. Reactivity

16. What is the product of the complete combustion of propane (C3H8)?

A. Carbon monoxide and water

B. Carbon and water

C. Carbon dioxide and water

D. Formaldehyde and water

17. What is the product of the reaction between methane and chlorine in the presence of UV light?

A. Methanol

B. Chloromethane

C. Carbon tetrachloride

D. Ethane

18. Which of the following statements accurately describes a sigma (σ) bond?

A. It is formed by the parallel overlap of p orbitals.

B. It is weaker than a pi (π) bond.

C. It is formed by the head-on overlap of atomic orbitals.

D. Rotation around a sigma bond is restricted.

19. Which of the following reactions proceeds via a carbocation intermediate?

A. SN2 reaction

B. SN1 reaction

C. E2 reaction

D. Free radical substitution

20. What is the relationship between enantiomers?

A. They are structural isomers.

B. They are superimposable mirror images.

C. They are non-superimposable mirror images.

D. They have different molecular formulas.

21. Which of the following carbocations is the most stable?

A. CH3+

B. CH3CH2+

C. (CH3)2CH+

D. (CH3)3C+

22. Which of the following molecules is chiral?

A. CH2Cl2

B. CH3CH2OH

C. CH3CHClCH3

D. CH3CHBrCl

23. Which reaction type is characteristic of alkanes?

A. Electrophilic addition

B. Nucleophilic substitution

C. Free radical substitution

D. Elimination

24. What is the IUPAC name for the compound with the structure CH3-CH(CH3)-CH2-CH2-CH3?

A. 2-Methylpentane

B. 4-Methylpentane

C. 2-Ethylbutane

D. Isopentane

25. What is the product of the reaction of propyne with two moles of H2 in the presence of a platinum catalyst?

A. Propene

B. Propane

C. 1,2-dibromopropane

D. No reaction

26. What type of reaction is the dehydration of alcohol to alkene?

A. Addition

B. Substitution

C. Elimination

D. Rearrangement

27. Which reagent is used for the bromination of alkenes?

A. HBr

B. Br2

C. KBr

D. NaBr

28. What is the configuration (R or S) of (S)-2-bromobutane?

A. R

B. S

C. Racemic

D. Meso

29. What type of isomerism is exhibited by cis-2-butene and trans-2-butene?

A. Structural isomerism

B. Functional group isomerism

C. Geometric isomerism

D. Optical isomerism

30. What is the IUPAC name of the simplest alkyne?

A. Ethyne

B. Propyne

C. Butyne

D. Methane